I used a LLM to create my database because it is not only a collection of words, but common phrases. Plus not only can the LLM format the database how I want it so it's interpretable to the program, it can build the database and included all the appropriate amount of duplicates.
The fact that you completely ignore that simply using a larger RSA key would both be faster and more secure than your approach, doesn't inspire confidence either.
The goal was to not use any modern crypto... Codebooks have been used for a very long time and are secure with proper key management.
This is an attempt at a modern codebook. It tackles most all of the shortcomings of previous iterations.
(It's also in python which is basically unusable. )
Haha.